Add registration valid until data in event.

event/event.go

@@ -39,6 +39,9 @@ type Registration struct {
 	// StatusCode holds the HTTP status code returned by the webhook registration.
 	StatusCode int
 
+	// Until holds the time the registration expires if applicable.
+	Until time.Time
+
 	// Err holds any error that occurred while performing the registration.
 	Err error
 }
@@ -51,6 +54,7 @@ func (r Registration) String() string {
 	buf.WriteString(fmt.Sprintf("  Duration:   %s\n", r.Duration.String()))
 	buf.WriteString(fmt.Sprintf("  Body:       '%s'\n", string(r.Body)))
 	buf.WriteString(fmt.Sprintf("  StatusCode: %d\n", r.StatusCode))
+	buf.WriteString(fmt.Sprintf("  Until:      %s\n", r.Until.Format(time.RFC3339)))
 	buf.WriteString(fmt.Sprintf("  Err:        %v\n", r.Err))
 	buf.WriteString("}\n")
 

event/event_test.go

@@ -25,6 +25,7 @@ func TestString(t *testing.T) {
 				"  Duration:   0s\n" +
 				"  Body:       ''\n" +
 				"  StatusCode: 0\n" +
+				"  Until:      0001-01-01T00:00:00Z\n" +
 				"  Err:        <nil>\n" +
 				"}\n",
 		}, {

listener.go

@@ -333,6 +333,7 @@ func (l *Listener) register(locked bool) error {
 	evnt.StatusCode = resp.StatusCode
 
 	if resp.StatusCode == http.StatusOK {
+		evnt.Until = evnt.At.Add(time.Duration(l.registration.Duration))
 		return l.dispatch(evnt)
 	}